replace paypal by bitcoin

HI,
I now use a social network with buddypress, armember and mycred. the payment solution is paypal.
A / I want to replace paypal by bitcoin if it is more advantageous?
How to compare the paypal costs with your solution? (do you get paid on transactions?)
B / is it easily possible to carry out the following scenario?
1) choice of payment in euros for an amount of a membership level (url coming from a row of the table is going to the payment gateway).
2) once the payment has been made (by the connected member), integration into a wordpress role (preferably with armember which manages the management of members) and if possible credit the mycred account?
Regards